ABSTRACT
The work here develops the concepts outlined by the author at the conference of this series in Manchester. A study is presented of an investigation into the generation of harmonics of shaft rotation speed in the vibration of misaligned multi-bearing rotor systems. The author challenges the conventional explanation that these harmonics arise principally from the bearing non-linearity. Whilst this may give rise to part of the observed behaviour, a more fundamental source of the harmonic terms arises from the properties of the coupling joining the rotors. The operation of a flange coupling is analysed with particular emphasis on the link between transmitted torque and lateral vibration. A calculation route is presented together with an example of the resulting response.
